Melissa Cregger

Melissa Cregger

Staff Scientist/Liane Russell Fellow


Melissa Cregger is a Staff Scientist/Liane Russell Fellow in the Biosciences division at Oak Ridge National Laboratory.  Dr. Cregger is an ecologist broadly interested in understanding microbial community dynamics across ecosystems, and how changes in microbial community structure may influence ecosystem level processes.  Specifically, she is interested in understanding the potential for changes in microbial diversity and composition to influence large scale nutrient fluxes and the health of associated host organisms, both plant and mammalian.  Her research spans scales from the molecule to the ecosystem level, taking advantage of modern techniques to fully understand microbial interactions. Dr. Cregger received her Ph.D. in Ecology and Evolutionary Biology in 2012 at the University of Tennessee under the guidance of Dr. Aimee Classen. After her Ph.D. she proceeded directly to a prestigious post-doctoral fellowship at the Carl Woese Institute for Genomic Biology at the University of Illinois in the Biocomplexity theme. There she expanded the focus of her work to examine host-microbe interactions in mammalian hosts. In 2014, she left the University of Illinois to begin a post-doctoral appointment with Dr. Chris Schadt at Oak Ridge National Laboratory. In 2015, she received a staff appointment at ORNL when she was awarded a Liane Russell Fellowship. 


Cregger MA, White BA, Braundmeier A (In prep – draft available upon request) Understanding changes in the cervical microbiome to predict endometriosis presence and recurrence. Target journal: Fertility and Sterility.

Cregger MA, Veach A, Schadt CW (In prep – draft available upon request) Deciphering plant microbe interactions across the Populus ecosystem. Target journal: Applied and Environmental Microbiology.

Classen AT, Sundqvist M, Henning JA, Newman GS, Moore JAM, Cregger MA, Moorhead L (2015) Direct and indirect effects of climate change on soil microbial and soil microbial-plant interactions: What lies ahead? Ecosphere 6:1-21.

Cregger MA, McDowell NG, Pockman W, Classen AT (2014) The impact of precipitation change on nitrogen cycling in a semi-arid ecosystem.  Functional Ecology 28:1534-1544.

Cregger MA, Sanders NJ, Dunn RR, Classen AT (2014) Microbial communities respond to experimental warming, but site matters. PeerJ 2:e358.

Wright P*, Cregger MA, Souza L, Sanders N, Classen AT (2014) Interactive effects of herbivory, nitrogen fertilization, and plant invasion on above and belowground community structure and function.  Ecology and Evolution 6:732-742.

McCord A, Chapman CA, Weny G, Tumukunde A, Hyeroba D, Klotz K, Koblings A, Mbora D, Cregger MA, White B, Leigh S, Goldberg TL (2014) Fecal microbiomes of non-human primates in western Uganda reveal species-specific communities largely resistant to habitat perturbation. American Journal of  Primatology 76:347-354.

Yeoman CJ, Thomas SM, Berg Miller ME, Ulanov AV, Torralba M, Lucas S, Gillis M, Cregger MA, Gomez A, Ho M, Leigh SR, Stumpf R, Creedon DJ, Smith MA, Weisbaum JS, Nelson KE, Wilson BA, White BA (2013) A multi-omic systems-based approach reveals metabolic markers of bacterial vaginosis and insight into the disease. Plos One 8:e56111.

Cregger MA, Schadt CW, McDowell NG, Pockman WT, Classen AT (2012) Soil microbial community response to precipitation change in a semi-arid ecosystem. Applied and Environmental Microbiology 78:8587-8594.

Lessard JP, Reynolds WN, Bunn WA, Genung MA, Cregger MA, Felker-Quinn E, Barrios-Garcia MN, Stevenson ML, Lawton M, Brown CB, Patrick M, Rock JH, Jenkins MA, Bailey JK, Schweitzer JA (2012) Equivalence in the strength of deer herbivory on above and below ground communities. Basic and Applied Ecology 13:59-66.

Genung MA, Lessard JP, Brown C, Bunn W, Cregger MA, Reynolds W, Felker-Quinn E, Stevenson M, Hartley A, Crutsinger G, Schweitzer J, and Bailey J (2010) Non-additive effects of genotypic diversity increase pollinator visitation. Plos One 5(1):  e8711.

Kardol P, Cregger MA, Campany C, and Classen AT (2010) Soil ecosystem functioning under climate change:  plant species and community effects. Ecology 91:767-781. 

Gustavson MD, Bourke-Martin B, Reilly D, Cregger M, Williams C, Mayotte J, Zerkowski M, Tedeschi G, Pinard R, and Christiansen J (2009) Standardization of HER2 Immunohistochemistry in breast cancer by automated quantitative analysis (AQUA). Archives of Pathology and Laboratory Medicine 133:1413-1419.

Gustavson MD, Bourke-Martin B, Reilly DM, Cregger M, Williams C, Tedeschi G, Pinard R, Christiansen J (2009) Development of an Unsupervised Pixel-based Clustering Algorithm for Compartmentalization of Immunohistochemical Expression Using Automated QUantitative Analysis. Applied Immunohistochemistry & Molecular Morphology 17:329-337.

Giltnane JM, Ryden L, Cregger M, Bendahl P.O, Jirstrom K, Rimm DL (2007) Quantitative measurement of epidermal growth factor receptor is a negative predictive factor for tamoxifen response in hormone receptor - Positive premenopausal breast cancer. Journal of Clinical Oncology 25:3007-3014.

Pozner-Moulis S, Cregger M, Camp RL, Rimm DL (2007) Antibody validation by quantitative analysis of protein expression using expression of Met in breast cancer as a model. Laboratory Investigation 87:251-260.

Shields JM, Thomas NE, Cregger M, Berger AJ, Leslie M, Torrice C, Hao HL, Penland S, Arbiser J, Scott G, Zhou T, Bar-Eli M, Bear JE, Der CJ, Kaufmann WK, Rimm DL, Sharpless NE (2007) Lack of extracellular signal-regulated kinase mitogen-activated protein kinase signaling shows a new type of melanoma. Cancer Research 67:1502-1512.

Cregger M, Berger AJ, Rimm DL (2006) Immunohistochemistry and quantitative analysis of protein expression. Archives of Pathology & Laboratory Medicine 130:1026-1030.

Dolled-Filhart M, McCabe A, Giltnane J, Cregger M, Camp RL, Rimm DL (2006a) Quantitative in situ analysis of beta-catenin expression in breast cancer shows decreased expression is associated with poor outcome. Cancer Research 66:5487-5494.

Dolled-Filhart M, Ryden L, Cregger M, Jirstrom K, Harigopal M, Camp RL, Rimm DL (2006b) Classification of breast cancer using genetic algorithms and tissue microarrays. Clinical Cancer Research 12:6459-6468.